You win, I win

Philip Kitcher

Organisms that contribute to the reproductive success of their species by doing things that decrease the size of their own brood appear to be inevitable losers in the Darwinian struggle. Since the 19th century, biologists have regarded the evolutionary possibility of altruism as an important theoretical puzzle, and in past decades, it has become clear that it can’t be solved by vague appeals to the idea that co-operative behaviour is good for the flock, the herd or the species. There are alternatives, however. If altruists direct their helpful behaviour towards relatives, then the genes associated with altruism may spread, because they are present in the beneficiaries and transmitted to their offspring; or if today’s altruist is tomorrow’s recipient, the present loss may be made up with interest. Models of kin selection and reciprocal altruism are widely regarded as solving the puzzle.

These explorations involve a special notion of altruism: biological altruists are organisms who contribute to the reproductive success of others at reproductive cost to themselves. By contrast, our everyday concept of altruism emphasises intentions, and we think of altruists as people who want others to thrive. Megalomaniacal spermdonors aside, few of us place reproductive considerations at the top of our list of priorities, so the biological focus on reproductive costs and benefits is alien to our broader vision of well-being. Moreover, biological altruism cares nothing about motives: indeed, it covers organisms not noted for the richness of their psychological lives – we can speak of altruistic behaviour in insects and even plants. Despite what some of the louder sociobiologists have claimed, an ability to account for the evolution of biological altruism does not have direct implications for psychological altruism, the kind of other-directedness that really matters to us.

Just as the puzzle of biological altruism has sometimes prompted Darwinians to deny that altruism exists in nature, so, too, there has been widespread scepticism about psychological altruism. Influential ideas in philosophy, economics and political theory have combined to offer a simple picture of human behaviour as directed towards maximising the satisfaction of the agent. Confronted with apparent examples of people who act to promote the welfare of others, fans of Homo economicus maintain that such people’s deep motives involve, if not the expectation of future benefit, at least the inner glow that comes from ‘doing good’. So, it’s suggested, we are creatures dedicated to our own pleasure and (the illusion of) altruism is most prominent when there are social means of inducing us to take pleasure in the happiness of others.

Elliott Sober and David Sloan Wilson are clear that there are two notions of altruism, as well as two challenges to its possibility, stemming from quite different sources, but their wide-ranging book is intended to tackle both. They begin with biological altruism, offering their own perspective on how this puzzle should be resolved, and discussing the ways in which natural selection of social structures may have figured in the history of our species. In the second half of Unto Others, they turn to psychological altruism, arguing that debates between those who believe that human beings are sometimes other-directed and their sceptical opponents cannot be settled either by philosophical arguments or by psychological experiments (at least, not by the kinds of psychological experiment typically designed by participants in the debates). They conclude by maintaining that natural selection would be expected to favour desires for the welfare of others based neither on the expectation of reciprocation nor on some ‘warm feeling’. Thus both types of altruism are made intellectually respectable.

Sober and Wilson offer a distinctive approach to the problem of biological altruism, one that attempts to incorporate the accepted solutions within a unified theory. For two decades, Sober, an internationally prominent philosopher of biology, has provided welcome clarification of the concept of natural selection, while, for an even longer period, Wilson, a well-known theoretical biologist, has campaigned to rehabilitate one of the most vilified views about the nature of selection. Unto Others opens with a manifesto for group selection.

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